In high school, Rainbow Dash didn't have much trouble remembering how great she was. She had the best friends one could hope for, nigh constant athletic victories, the unshakable conviction she was better than Applejack, and the fact she was a, fairly active, super hero to remind her that she was awesome.
High school ended, the band broke up, the magical threats died down, everyone went to different colleges, and it became harder and harder for Rainbow to convince herself that she had value. Recently, she stopped replying to messages from her friends; she's pretty sure they'll be better off without her.
Fluttershy is getting worried, but she's too far away to check on Rainbow herself. Sunset Shimmer, on the other hand, is only a two hour drive away.
In theory, this is being written for the Pride and Positivity event. In practice whether it's actually in time depends on what timezone one happens to be in.
Usually, my depression is preventing me from writing these days. The exception to that seems to be the 11th hour. In this particular case, that's literal as well as figurative.
It probably says something about my state of mind that the story I thought up for an event with "positivity" in the name is one about debilitating depression. I did check the rules, though; this counts.